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A Breadth Averaged Numerical Model for Suspended Sediment Transport in Hooghly Estuary,East Coast of India 总被引:2,自引:0,他引:2
Sinha P. C. Guliani Pragya Jena G. K. Rao A. D. Dube S. K. Chatterjee A. K. Murty Tad 《Natural Hazards》2004,32(2):239-255
Sedimentation is of vital concern in the conservation, development and utilization ofour soil and water resources. The suspended sediment in estuarine waters is hazardousto navigation in estuaries, which have important ports and harbours. A breadth-averagednumerical model to study circulation and sediment transport is presented in this paper.The model is applied to Hooghly estuary, along the east coast of India. The model is fullynon-linear and uses a semi-explicit finite difference scheme to solve mass, momentum andadvection diffusion equation for suspended sediments in a vertical plane. The erosion anddeposition have been computed by empirically developed source and sink terms in thesuspended sediment equation. 相似文献
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Pragya Pandit Shailendra Kumar Pargin Bangotra Rohit Mehra Manoj Mohapatra Madhuparna Roy A K Singh 《Journal of Earth System Science》2018,127(8):110
The structural and spectroscopic characteristics of phosphatic ferruginous shale samples from the Bijawar Group rocks from Sagar District of Madhya Pradesh (India) have been probed for identification of uranium species. Fluorapatite (\(\hbox {Ca}_{5}\hbox {(PO}_{4})_{3}\hbox {F}\), FAP) and haematite (\(\upalpha \)-\(\hbox {Fe}_{2}\hbox {O}_{3}\)) were identified as the main phases in the separated mineral concentrates. The photoluminescence (PL) and X-ray absorption near edge spectroscopy (XANES) studies pointed to a strong experimental evidence of both U(IV) and U(VI) oxidation states in the mineral concentrate portion obtained from the same parent host rock. The PL spectrum has confirmed the charge transfer (f–d) transition bands in UV and near-UV regions with emission peaks at ca. 290, 313, 336, 399 and 416 nm, which has been attributed to the substitution of \(\hbox {Ca}^{2+}\) ions by U(IV) in FAP and broad structureless emission due to stabilisation of U(VI) as \(\hbox {UO}_{6}^{6-}\) in haematite. Time-resolved spectroscopy studies have revealed biexponential decay components lasting 2–5 ns for U(IV) species and \(10\,\upmu \hbox {s}\) for U(VI) species. These characterisations revealed the fundamental information about the oxidation state and form of uranium in this region. Remediation measures for the Bijawar region are also suggested. 相似文献
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